Radiative and Seesaw Threshold Corrections to the S3S_3 Symmetric Neutrino Mass Matrix

We systematically analyze the radiative corrections to the $S_3$ symmetric neutrino mass matrix at high energy scale, say the GUT scale, in the charged lepton basis. There are significant corrections to the neutrino parameters both in the Standard Model (SM) and Minimal Supersymmetric Standard Model (MSSM) with large tan$\beta$, when the renormalization group evolution (RGE) and seesaw threshold effects are taken into consideration. We find that in the SM all three mixing angles and atmospheric mass squared difference are simultaneously obtained in their current 3$\sigma$ ranges at the electroweak scale. However, the solar mass squared difference is found to be larger than its allowed 3$\sigma$ range at the low scale in this case. There are significant contributions to neutrino masses and mixing angles in the MSSM with large tan$\beta$ from the RGEs even in the absence of seesaw threshold corrections. However, we find that the mass squared differences and the mixing angles are obtained in their current 3$\sigma$ ranges at low energy when the seesaw threshold effects are also taken into account in the MSSM with large tan$\beta$.Comment: 20 Pages, 2 Figures and 2 Table

Renormalization Group Evolution of Neutrino Parameters in Presence of Seesaw Threshold Effects and Majorana Phases

We examine the renormalization group evolution (RGE) for different mixing scenarios in the presence of seesaw threshold effects from high energy scale (GUT) to the low electroweak (EW) scale in the Standard Model (SM) and Minimal Supersymmetric Standard Model (MSSM). We consider four mixing scenarios namely Tri-Bimaximal Mixing, Bimaximal Mixing, Hexagonal Mixing and Golden Ratio Mixing which come from different flavor symmetries at the GUT scale. We find that the Majorana phases play an important role in the RGE running of these mixing patterns along with the seesaw threshold corrections. We present a comparative study of the RGE of all these mixing scenarios both with and without Majorana CP phases when seesaw threshold corrections are taken into consideration. We find that in the absence of these Majorana phases both the RGE running and seesaw effects may lead to $\theta_{13}<$ 5$^\circ$ at low energies both in the SM and MSSM. However, if the Majorana phases are incorporated to the mixing matrix the running can be enhanced both in the SM and MSSM. Even by incorporating non zero Majorana CP phases in the SM, we do not get $\theta_{13}$ in its present 3$\sigma$ range. The current values of the two mass squared differences and mixing angles including $\theta_{13}$ can be produced in the MSSM case with tan$\beta$ = 10 and non zero Majorana CP phases at low energy. We also calculate the order of effective Majorana mass and Jarlskog Invariant for each scenario under consideration.Comment: Discussion modified in Sec 4, references added. Version to appear in Nucl. Phys.

MGNREGA and Economic Empowerment of Women - Study of Indian Women

Mahatma Gandhi National Rural Employment Guarantee Act (MGNREGA) was enacted in India in 2005.It guarantees 100 days of work and ensures at least 33 per cent of the women participation. Even though MGNREGA has played a substantial role in economically empowering women, it faces major challenges that restrict their participation. This essay dwells into the complexities faced by women in India and exposes various factors that limit the success of MGNREGA. The study finds that tenacious social norms, continued illegal presence of contractors, lack of proper childcare facilities and delayed payments are the crucial factors that restrict women participation. Policy implications for Indian Government are also put forward

Conflict Resolution Styles of XI Grade students in Delhi: An Experimental Study

The purpose of this study was to investigate the influence of interventions conducted to bring a positive change in conflict resolution styles among students of Class XI. Conflict resolution style was measured by Thomas- Kilmann Mode Instrument. Forty five students of Standard XI participated in the study. A pre-test and post-test experimental design was used. A pre-test was carried out in the beginning of the interventions to determine the conflict resolution style used by participants in their inter-personal conflicts. The interventions, in the form of group activities like removing the blocks in communication, effective usage of non-verbal communication, importance of listening, group discussion on anger management, and inculcation of constructive social skills were conducted. A post-test was carried out to measure the effects of interventions on participants’ conflict resolution styles. Results indicated that the conflict resolution style of the group was modified and transformed into a mature and constructive way of dealing with conflicts. Keywords: Conflict, Conflict Resolution, Conflict Resolution Styles, Communication. DOI: 10.7176/JEP/10-4-0

Minimal extension of tri-bimaximal mixing and generalized Z_2 X Z_2 symmetries

We discuss consequences of combining the effective $Z_2\times Z_2$ symmetry of the tri-bimaximal neutrino mass matrix with the CP symmetry. Imposition of such generalized $Z_2\times Z_2$ symmetries leads to predictive neutrino mass matrices determined in terms of only four parameters and leads to non-zero $\theta_{13}$ and maximal atmospheric mixing angle and CP violating phase. It is shown that an effective generalized $Z_2\times Z_2$ symmetry of the mass matrix can arise from the $A_4$ symmetry with specific vacuum alignment. The neutrino mass matrix in the considered model has only three real parameters and leads to determination of the absolute neutrino mass scale as a function of the reactor angle $\theta_{13}$.Comment: References added, accepted for publication in Phys. Rev. D (Rapid Communication

Neutrino Mass Matrices with a Texture Zero and a Vanishing Minor

We study the implications of the simultaneous existence of a texture zero and a vanishing minor in the neutrino mass matrix. There are thirty six possible texture structures of this type, twenty one of which reduce to two texture zero cases which have, already, been extensively studied. Of the remaining fifteen textures only six are allowed by the current data. We examine the phenomenological implications of the allowed texture structures for Majorana type CP-violating phases, 1-3 mixing angle and Dirac type CP-violating phase. All these possible textures can be generated through the seesaw mechanism and realized in the framework of discrete abelian flavor symmetry. We present the symmetry realization of these texture structures.Comment: To appear in Phys. Rev.